Project Summary We propose to build a next generation crowdsourcing platform (code named ?FlyWire?) for mapping the fly connectome using transmission electron microscopy images that were acquired at Janelia Research Campus. FlyWire will depart from EyeWire, a previous crowdsourcing platform, in two major ways: (1) Much higher throughput will be attained by leveraging the latest in deep learning. (2) FlyWirers will consist mainly of fly neuroscientists, while EyeWirers were primarily nonscientists. Once minimum usability and functionality are achieved with the Murthy lab as the pilot users, FlyWire will be opened up to the entire Drosophila neurobiology community. All reconstructions will be shared by the community. To motivate productivity and accuracy, the reconstruction of a neuron and its outgoing synapses will be reported through a ?micropublication,? with a quantitative formula for assigning authorship. To guide the development of FlyWire, the Murthy lab will reconstruct all presynaptic and postsynaptic partners of a subset of central brain neurons involved in sensory processing and behavior. We will use the connectome of these neurons as a launching point to investigate how featureselective sensory responses arise and how they are decoded to change behavior. We will also create software tools for matching FlyWire neurons with light microscopic reconstructions of neurons. The proposed project will complement Janelia?s efforts to obtain the fly connectome with FIBSEM imaging. Janelia?s final FIBSEM connectome is estimated to take up to five years, though draft connectomes should become available sooner. FlyWire will provide Drosophila neuroscientists with badly needed information about connectivity in the years before the FIBSEM connectome becomes available. Multiple connectomes will enable the study of variability across individuals and between sexes (FlyWire will reconstruct a female brain, while the first FIB SEM connectome will be of a male brain.)